By Madeline Chambers BERLIN (Reuters) - A pensioner has started digging in Germany's western Ruhr region for the Amber Room, a priceless work of art looted by Nazis from the Soviet Union during World War Two and missing for 70 years, but says he needs a new drill to help him. Dubbed the Eighth Wonder of the World, the Amber Room was an ornate chamber made of amber panels given to Czar Peter the Great by Prussia's Friedrich Wilhelm I in 1716. Now 68-year-old pensioner Karl-Heinz Kleine says he thinks the chamber is hidden under the town of Wuppertal, deep in western Germany's industrial Ruhr area. After analyzing the evidence, Kleine has concluded that Erich Koch, who was the Nazis' chief administrator in East Prussia, may have secretly dispatched it to his home town.